PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 343 



with dotted margins, no median dark line on back ; sides of head bright 

 silvery ; top of head dusky posteriorly ; caudal and dorsal fins dotted 

 with black, these dots forming two faint blotches at base of caudal ; a 

 series of black dots between anal and caudal fins. 



About 10 specimens were obtained in the Astillero at Mazatlan, the 

 largest 2J inches long. It is apparently less abundant than the other 

 species of this genus in company with which it is found. 



The types are numbered 28120 on the register of the National 

 Museum. 



6. Stolephorus curtus, sp. nov. (29242.) 



Body more compressed and elevated than In S. isclianus; dorsal out- 

 line nearly straight, the ventral scarcely curved except anteriorly; cau- 

 dal peduncle deep : belly in front of ventral fins sharply compressed, 

 carinate and serrulate. Head short and high, its depth at occiput seven- 

 tenths its length; snout blunt, not much produced; tip of lower jaw in 

 front of eye ; maxillary tapering to a sharp point, which usually does 

 not quite reach gill-opening ; both jaws with very minute teeth, per- 

 ceptible towards symphysis of lower jaw, but not laterally. Opercle 

 shortish; cheeks broadly triangular. Gill-rakers on upper limb longest, 

 about two-thirds diameter of orbit. Eye large, contained 2f to 3:| times 

 in length of head. 



Origin of dorsal fin midway between base of middle rays of caudal 

 •and middle of pupil ; the fin short and rather high, its base but little 

 more than one-half length of head ; the last rays not produced. Origin 

 of anal fin under middle or anterior third of base of dorsal ; the base of 

 the fill moderate, varying from nearly as long as, to a little longer than, 

 head. Caudal short, less than length of head; the lower lobe longest; 

 the fin moderately forked ; the middle rays about two-fifths the length 

 of the longest. Pectorals very short and rounded, variable in length, 

 but usually not reaching base of ventrals. Scales thin, caducous. 



D. 11 or 12 ; A. 22 or 23 ; L. lat. 35 ; L. transv. 5. Head, 4^ in length ; 

 depth, 4|. 



Color translucent ; sides with a silvery luster ; top of head dusky ; 

 sides of head and a faint streak along sides of body with silvery pig- 

 ment ; the streak is somewhat indistinct, especially forwards, where it 

 often disappears ; basal half of dorsal fin punctate with black and yel- 

 low dots ; a double series of these dots along base of fin, running back 

 to base of caudal ; caudal not black margined ; base of anal thickly 

 punctate, a series of dots usually extending back to caudal fin ; paired 

 fins immaculate; tip of snout yellowish, without black specks; no dark 

 line in front of dorsal fin. 



Many specimens 2^ inches long were obtained at Mazatlan, where it 

 is common in the muddy waters of the Astillero. The types are num- 

 bered 29242 on the register of the National Museum. 



